Every three weeks, Dr. Jennifer Pate, 47, receives life-saving intravenous immunoglobulin infusions. Without them, her immune system is defenseless against potentially lethal infection.

Without them, her immune system is defenseless against potentially lethal infection. Although the Texas woman’s medical condition has come with setbacks, she has turned her diagnosis into something positive: a means to help others cope with chronic illness as a psychiatrist.

Pate, who lives in Houston, has common variable immune deficiency (CVID), which is thought to affect between 1 in 25,000 to 1 in 50,000 people worldwide. Unlike those with a healthy immune system, Pate’s antibodies don’t kick into gear when her body is exposed to harmful bacteria, leaving her at risk of recurrent infection and death.

Despite enduring numerous battles with pneumonia, seven bouts with shingles, and a life-threatening infection that left her deaf in one ear, Pate has given back to the doctors who have treated her for the past 30 years.

In 2014, she established a fund at Texas Children’s Hospital, where she’s been treated since childhood, to help others with immune deficiency cover their medical costs. She has also served as chief of psychiatry at Baylor St. Luke’s Medical Center since 2006.

Puzzled by a mysterious infection

Ever since Pate was 11, she has struggled with recurrent sinus and ear infections, as well as discomfort from allergies and asthma. But it wasn’t until she was a senior in high school that her pediatrician really took pause. Test results showed Pate had somehow been exposed to giardia— a parasite typically transmitted through beavers and mountain streams, and common among hikers— that causes a gastrointestinal infection. It was a peculiar infection to find in a teenager who spent her free time playing tennis in Houston, Pate recalled her physician thinking.

At a loss for what to do, Pate’s pediatrician sent her to Texas Children’s Hospital, where doctors measured her antibodies and found that her lymphocyte B cells weren’t behaving properly. Typically, when B cells mature, they become antibodies, which enable the body to fight infection. But Pate’s B cells appeared to be abnormal: Her immunoglobulin G levels were lower than they should’ve been, and the cells that were left weren’t functioning properly. The diagnosis: CVID, a condition that typically appears in the second decade of a person’s life.

In the 30 years since, Pate has returned regularly to Texas Children’s to receive life-saving intravenous immunoglobulin G (IVIG) infusions that boost her antibody counts and help neutralize the effects of CVID. Pate could receive the infusions portably through a home health care agency, subcutaneously— via a shot injected into the layer of fat between the skin and muscle— but because that method induces headaches and physical discomfort for Pate, she receives them by IV instead.

“She’s not an anomaly,” Imelda Celine Hanson, a professor of pediatrics at Texas Children’s Hospital, and the doctor who administers Pate’s infusions, told FoxNews.com. “Her reactions are not something we see typically in our patients, but they have been described in many patients with CVID.”

The IVIG infusions, which are extracted from a pool of donated human plasma, have only minor side effects, such as bruising and pain at the site of injection.

In addition to CVID, Pate has autoimmune disease, which is found in about 25 percent of CVID patients, according to the National Institutes of Health (NIH). In autoimmune disease, the immune system can’t tell healthy tissue and harmful substances, known as antigens, apart, so the body reacts by destroying normal tissue. Autoimmune disease may leave Pate more at risk for developing lupus, arthritis or autoimmune thyroiditis in the future, Hanson said. Some medications aren’t compatible with autoimmune disease and may be harmful, so Pate’s doctors must take extra care.

“From a CVID perspective, she’s definitely a challenging patient,” Hanson said. “She has the best health when she has a good communicating team of health care providers.”

The life-saving infusions have enabled Pate to lead a relatively normal life— still with a high risk of infection but with one that is dramatically reduced.

“I must say, we can’t restore Mother Nature, but we can do a pretty good job with the infusions of IVIG,” William Shearer, a pediatrics and immunology professor at Texas Children’s, who first diagnosed Pate with CVID, told FoxNews.com.

Living with CVID

When Pate was diagnosed with CVID, her dreams of becoming a professional tennis player were all but extinguished, which left her unsure of what to do. The avid young player had never considered any other career.

While in and out of the hospital for recurrent pneumonia during her freshman year of high school, Pate developed an interest in medicine, from her exposure to scientific subjects at school as well as her treatment at Texas Children’s. Her older brother, David, 58, also studied medicine and inspired Pate to follow suit. But because of CVID, many fields of medicine would be off limits to her.

“When she said she was going to be a doctor, I was terrified of her being around all those illnesses, knowing that it could be a major problem for her,” Pate’s mother, Charlene Pate, 78, told FoxNews.com, “but she was willing to face that.”

It turned out that psychiatry, a less risky field compared to those like surgery or pediatrics with respect to the chance of infection, was more interesting to Pate anyway. She went to the University of St. Thomas in Houston then graduated from the University of Texas Medical Brach with her degree in medicine.

“I care more about the people behind the illness than the actual symptoms or the medications involved, and I like to get to know people and help them with whatever experience they’re dealing with,” Pate said, “so psychiatry ended up being a great fit for me, and I think it’s in generally a fairly safe way for me to practice medicine.”

Counseling others through experience

As a psychiatrist at Baylor St. Luke’s Medical Center, in Houston, Pate meets primarily with patients who are dealing with chronic or terminal illness, including those in line for organ transplants.

“I think my own experience with my own chronic illness has made me a much better physician,” Pate said. “My patients are always surprised at how well I understand and get what they’re going through.”

But working in a clinical setting with CVID still poses challenges. Pate must advise patients to reschedule their appointments if they have cold or flu symptoms.

Three years ago, Pate contracted a life-threatening infection from a community pool she and her doctors thought was safe, and she now has a drain attached to her neck that she covers with a scarf. The drain increases her risk for exposure to new infections, but it’s necessary because it allows fluid from an infection-created hole in her mastoid, the temporal bone behind the ear, to escape. The drain is meant to prevent another hole from forming. She must get the drain replaced bi-monthly and takes seven daily doses of antibiotics to treat the infection.

To reduce the chance of further infection, Pate sees patients only in an outpatient setting and avoids large crowds, where infection risks are high.

“I’ll try to go crowded places at the least crowded time. One of the things I don’t fudge on is I always go Christmas shopping in New York. That’s an exception. My mom and I have done that for decades,” Pate said.

Moving forward and staying positive

Today, Pate copes with recurrent bouts of shingles, a not uncommon side effect of CVID. So far, she has battled seven rounds of the condition. According to the Mayo Clinic, shingles is caused by the same virus as chicken pox, the varicella-zoster virus, and presents as a painful rash with blisters that often wraps around the torso. Although shingles isn’t life-threatening, “it’s horrifically painful— those TV commercials are accurate,” Pate said.

Despite the physical discomfort, Pate manages to speak routinely at medical meetings on behalf of Texas Children’s. She and her mother also recently established a fund, of an undisclosed amount, at Texas Children’s to help other patients with immune deficiency cover their medical bills, and to help the hospital’s nurses and doctors attend educational conferences.

“She’s a busy physician and has her own needs, and is still willing to take the time out when she already needs a lot, but she’s still willing to give a lot,” Hanson said.

Shearer, who has watched Pate grow up, said Pate had a positive attitude even during her adolescence, so he isn’t surprised she’s used it to lift other people’s spirits.

“Her attitude is what you like to see in a patient— they’re not defeated; they’re going up against what they have,” Shearer said. “She sees the sickest patients, who from time to time do get down, and when they hear her story, they sober up and say, ‘If this woman can do what she’s done with her life, I can do something with mine.’”

To further help people cope with chronic illness, Pate has written patient education articles and had them published in medical magazines. Among the topics she’s covered are how chronic illness impacts marriage, and how to cope with awaiting and receiving an organ transplant.

She no longer swims, and she has trouble with tennis because playing the sport well depends heavily on hearing how the ball comes off the other player’s racket, which is difficult with only one healthy ear.

But Pate has other plans for the future. She hopes to write a memoir on living with chronic illness and counseling others with it, as she hasn’t come across a memoir that tackles the event from both perspectives.

“I was certainly a patient who saw my physicians as perfect and thought that they certainly couldn’t have anything wrong with them,” Pate said, “and I think [my story] sends an important message to patients that it’s possible to overcome a lot of things.”